The present invention relates to component mounters and mounting methods for mounting, for example, electronic components on a board.
A component mounter for mounting electronic components such as semiconductors on a board is equipped with a component feeder carriage in which numerous parts feeders such as tape feeders for storing components are aligned.
The component mounter repeats the mounting operation of picking up components from these parts feeders using its transfer head, and placing them on the board. In order to improve the efficiency of this mounting operation, multi-nozzle transfer head, in which two or more suction nozzles for holding components are aligned, is often used. Conventional alignment of suction nozzles in the multi-nozzle transfer head includes the series nozzle type, in which two or more suction nozzles are aligned linearly in a single line; and the rotary type in which two or more suction nozzles are disposed circumferentially.
The mounting operation takes place by moving the transfer head by using a moving device such as an XY table. However, the moving shafts composing the XY table incorporate mechanical error caused by pitch error of the ball screw.
Accordingly, the move command value for each shaft from the controller does not always result in the actual position being attained. Positional deviation specific to each point on the board exists. The mounter thus executes calibration for identifying the positional deviation specific to each mounting point on the board in advance to compensate for the deviation. More specifically, a board recognition camera captures an image of a calibration board in which calibration measuring points are provided on a grid at the time of machine startup and maintenance. The position of each measuring point detected by capturing the image is compared with the position in the control data for identifying the dislocation unique to each mounting point. During the actual mounting operation, the moving device is driven while compensating for the identified dislocation.
However, a conventional transfer head as described above has the following disadvantages in mounter structure and mounting efficiency.
First, the series nozzle type requires greater alignment length with increasing number of nozzles. This leads to a longer horizontal movement stroke for moving the transfer head within the mounter, increasing machine space and costs. In addition, a larger number of nozzles unavoidably results in buildup of pitch error between suction nozzles. Larger pitch error causes more frequent suction errors while vacuum-holding two or more components picked up at the same time from the component feeder carriage (multiple parts feeders) by two or more suction nozzles. The resulting failure of simultaneous component pickup may reduce mounting efficiency. This lower feasibility of simultaneous pickup is also a disadvantage of the rotary transfer head.
Second, many different types of components are mounted on the same board, and shapes and sizes also differ. Accordingly, the suction nozzle which vacuum-holds and picks up these components need to be designed to pick up specific types of components. However, it is difficult to efficiently dispose two or more suction nozzles for components with different sizes and shapes in a conventional multi-nozzle transfer head. This restricts the types of components that can be mounted using the same mounter, impeding the improvement of mounting efficiency.
Third, a multi-nozzle transfer head also requires the aforementioned calibration process. However, a complete set of calibration data may not be obtainable depending on where the camera is positioned on the series nozzle transfer head when the board recognition camera installed in the series nozzle transfer head is used for calibration.
The present invention aims to offer a space-saving and compact component mounter and mounting method which allows to increase the mounting efficiency by improving the feasibility of simultaneous pickup of several components.
The present invention also aims to offer a component mounter and mounting method that enables processing of highly precise calibration data by appropriately placing a board recognition camera with respect to a transfer head to which two or more nozzles are provided.
The present invention further aims to offer a component mounter and mounting method which improves the mounting efficiency by broadening the types of applicable components.
The component mounter of the present invention includes:
(a) a plurality of parts feeders aligned in a component feeder carriage; and
(b) a transfer head for picking up components from the parts feeders and mounting them on a board. The transfer head has two or more suction nozzles for vacuum-holding components.
Suction nozzles are aligned at a predetermined basic pitch, alongside the setting direction of the parts feeders, in two or more lines.
This configuration allows to make the mounter smaller, and also achieves more efficient component mounting by improving the feasibility of simultaneous pickup of several components.
Another component mounter of the present invention includes:
(a) a plurality of parts feeders aligned in a component feeder carriage; and
(b) a transfer head for picking up components from the parts feeders and mounting them on a board. The transfer head has two or more suction nozzles for vacuum-holding components.
The suction nozzles are of different sizes, and they are aligned at a predetermined basic pitch and/or simple multiple of basic pitch, alongside the setting direction of the parts feeders, in two or more lines.
This configuration broadens the types of applicable components using the same mounter, increasing the component mounting efficiency.
The component mounting method of the present invention includes the step of simultaneously picking up two or more components from the parts feeders using a transfer head of a mounter described next.
The mounter for implementing the mounting method of the present invention includes a plurality of parts feeders aligned in a feeder carriage; and a transfer head for picking up components from the parts feeders and mounting them on a board. The transfer head has two or more suction nozzles for vacuum-holding components.
The suction nozzles are aligned at a predetermined basic pitch, alongside the setting direction of the parts feeders, in two or more lines. The nozzle lines are aligned perpendicular to the alignment direction of nozzles in each nozzle line.
This method enables to save machine installation space and make the mounter more compact. At the same time, components can be mounted with better efficiency by improving the feasibility of simultaneous pickup of two or more components.
Another component mounting method of the present invention relates to the process of picking up components from two or more parts feeders aligned in the component feeder carriage by using the transfer head.
The above transfer head has two or more nozzles for vacuum-holding components, and these nozzles are aligned at a predetermined basic pitch, alongside the parts feeders, in two or more lines.
The mounting method of the present invention includes the next steps.
(a) Capturing of an image of a calibration board using a camera which is disposed approximately in line with a nozzle line at the component feeder carriage side in several nozzle lines, or at nearer to the head attachment base side from the nozzle line. The camera integrally moves with the transfer head by a moving device for moving the transfer head.
(b) Processing of calibration data for the moving device based on image capturing results.
The above method enables to capture images in the entire calibration area.
Another component mounting method of the present invention also relates to the process of picking up components from two or more parts feeders aligned in the component feeder carriage and mounting them on a board by using the transfer head.
The above transfer head for implementing the mounting method of the present invention has two ore more suction nozzles with different sizes for vacuum-holding components. These nozzles are aligned at a predetermined basic pitch and/or an simple multiple of basic pitch, alongside the parts feeders, in two or more lines.
The mounting method of the present invention includes the step of picking up several components with different sizes using this transfer head.
This method broadens the types of applicable components using the same mounter, improving the component mounting efficiency.